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A series of tetra(biphenyl-4-yl)phthalimide (TBPPI) derivatives with different N-substituents (n-butyl, phenyl, p-methyl phenyl, and p-acetyl phenyl moieties for compounds 7–10, respectively) were prepared to examine their fluorescent behavior under various conditions. The chemical structure of compound 7 has been successfully confirmed by single crystal X-ray diffraction analysis. The photoluminescence (PL) spectra in different ratios of CH2Cl2/EtOH mixture solutions revealed that compounds 7 and 8 exhibited both aggregation-induced emission (AIE) and aggregation-caused quenching (ACQ) behaviors, while compounds 9 and 10 displayed AIE and aggregation-induced emission enhancement (AIEE) properties, respectively.

Addition reaction of 3,4-dihydroisoquinolines with γ-hydroxy-α,β-unsaturated ketones furnished a variety of diastereomerically pure oxazolo[2,3-a]tetrahydro-isoquinolines, which could be purified by either recrystallization or solvent evaporation. The reaction proceeded smoothly under “green” conditions without an additive and catalyst, giving the target molecules in good to excellent yields.

We have successfully demonstrated a single-crystal field-effect transistors (FETs) based on an asymmetric perylenetetracarboxylic diimide (a-PDI) compound with polystyrene (PS)/SiO2 bilayer as gate dielectric. The single crystals are in-situ grown on substrate from simple solution evaporation method, thus may be suitable for large area electronics applications. The PS modified gate dielectric could minimize charge trapping by the hydroxyl groups of the SiO2 surface. The resulting solution processed single crystals transistors are characterized in ambient air, and exhibited maximum electron mobility of ca. 1.2 cm2 V−1 s−1 and high Ion:Ioff > 105.

Thionation and fluorination of pyromellitic diimides (PyDIs) increased the electron mobility and on/off ratio of the original diimides by two orders of magnitude and improved the threshold voltage and air-stability of diimide compounds.